A generally known stop valve for a compressed-air bottle for diving applications is, in one design, in the form of a single connection valve consisting of one valve body with three connection adapters. The central connection adapter is a connection adapter for a gas container and, as such, it is provided with threads for the connection of the gas container, being as a rule an outside thread. The two additional connection adapters which are offset in axial direction are made in the form of outlet and connection adapters and as spindle drive receiving adapters and are axially offset, lying in a transversal plane radial to the axis of the gas container connection adapter. A central gas supply bore is provided, starting at the gas container connection adapter and going into the transversal area and then a radial gas supply bore to the bottom area of the spindle drive receiving adapter, where a valve seat with a gas chamber surrounding it is formed in the bottom area. This is the gas supply going from the pressurized-gas container to the valve seat.
A manually operated spindle drive with a seat seal that is adjustable relative to the valve seat is tightly installed in the spindle drive receiving adapter and held in place by screw attachment. In a known design the spindle drive is provided with a screw connection element with a rotatable upper spindle and a lower spindle with seat seal that is coupled to the upper spindle and is adjustable relative to the valve seat. An outlet gas line goes from the valve seat gas chamber to the bottom area of the outlet connection adapter. Such a stop valve is designed especially for a compressed-air bottle for diving applications, whereby demand oxygen system is connected to the outlet connection adapter.
Also generally known is a double connection valve of similar design having two valve units in one valve body that can be closed and opened independently of each other. For this purpose two outlet connection adapters and two spindle drive receiving adapters with associated valve seats and spindle drives are provided which are supplied via a gas container connection adapter. One outlet connection adapter and one associated spindle drive receiving adapter are installed in a known embodiment with 90° offset, so that a cross-shaped adapter arrangement results. It is known in this case to provide the outlet connection adapters across from each other in a so-called parallel valve arrangement or in a corner valve arrangement with 90° offset. When used as a stop valve on compressed-air bottles in diving applications the double connection valve has the function of providing the possibility to use two demand oxygen systems that can be actuated independently of each other are connected, and can in particular be used independently of each other and alternatively in case of trouble, as a safety measure. With stop valves for a portable pressurized-gas container, in particular with compressed-air bottles for diving applications, different containers with different connection threads are brought on the market. In particular different thread sizes as well as metric threads or threads in inches are used. Also, such different connection threads for the connection of demand oxygen systems are commonly sold, whereby double connection valves, corner valves or parallel valves are used depending on the individual case and in order to cover all possible variations of connection valves and geometrical layouts a great number of different designs of stop valves are required. This requires on the one hand high manufacturing expenditures and on the other hand extensive stock management of different designs together with costly logistics. In addition the manufacturing technology for the production and machining of the valve seats in the bottom area of the spindle drive receiving adapters is expensive. In case of problems with tightness due to defects on the valve seat, in particular due to wear, at least the entire valve body of the stop valve must be replaced.